Translation guide
The English word 'empire' refers to a large, powerful political unit, often ruled by an emperor or empress, or a dominant organization. In Japanese, the most common equivalent is 帝国 (ていこく), but other terms exist for specific historical empires or metaphorical uses.
A large, sovereign state ruled by an emperor or empress, often consisting of multiple territories.
The standard term for 'empire' in a political sense. Used for historical empires like the Roman Empire or the British Empire.
ローマ帝国は広大な領土を持っていた。
The Roman Empire had vast territories.
大英帝国はかつて世界中に植民地を持っていた。
The British Empire once had colonies all over the world.
A literary or historical term for an empire, often used in pre-war Japanese contexts to refer to Japan itself. Rare in modern usage.
大日本皇国
The Empire of Great Japan (historical name)
A large, powerful corporation or group of companies controlled by one person or entity.
Used metaphorically for a business empire, similar to English. Often combined with the founder's name or industry.
彼はメディア帝国を築き上げた。
He built a media empire.
Literally 'corporate empire', explicitly refers to a business empire.
彼の企業帝国は世界中に広がっている。
His corporate empire spans the globe.
A domain or sphere of influence, not necessarily political or commercial.
Can be used figuratively, as in 'an empire of the mind'.
彼は精神の帝国を築いた。
He built an empire of the mind.
Pattern: [noun]の帝国, meaning 'empire of [noun]'. Productive for metaphorical uses.
知識の帝国
empire of knowledge
While 帝国 can be used metaphorically, it may sound grandiose or unnatural in casual contexts. For describing a large company, 大企業 (だいきぎょう, large corporation) or グループ (group) might be more natural unless emphasizing the 'empire' aspect.